Underwater torch and method therefor



E. ELLSBERG UNDERWATER TORCH AND METHOD THEREFOR Filed Dec. 20, 1927lNvENToR fda/ard' f/lsberg.

BY Kaw/@ATTORNEY Patented Sept. 22, 1931 UNITED STATES EDWARD. ELLSBERG,OF WESTFIELD, NEW JERSEY UNDERWATER TORCH AND METHOD THEREFORApplication led December 20, 1927. Serial No. 241,387.

- My present invention relates more particularly to blow torches forcutting and for autogenous welding of metal, It involves discoverieswhereby it is made commercially 6 practical to cut metal under walterand particularly toperform such operation in a.

reliable manner on a commercial basis at great depths. As is well known,metal cutting torches l utilize a mixture of fuel gas and pure oxygendischarged in a composite jet llame adapted to locally heat the metal toa high temperature, whereupon a. jet of pure oxygen is blown through thellame onto the hot spot to melt or burn away the metal, the operationbeing carried on progressively along the line of the desired cut. In thepresent state of the art, acetylene and otheI` of the higher hydrocarbongases or mix- 9 tures thereof with hydrogen, are used as the fuelconstituent of the jet, because of their great fuel value per unitvolume.

It has long been proposed and often attempted to perform similar metalcutting operations under water, as in submarine construction and shipsalvage work, by surrounding the blow pipe flame with a sheath of airfor the purpose of isolating the llame and excluding the water from the5 surface of the metal on which the llame is directed. In connectionwith my work in the United States Navy, I have investigated and testedall of the most -romising of the suggested ways of doing t is, with theresult that all of them have proved unreliable and frequently dangerousunder relatively small depth pressures, say, 15 to 30 feet and all ofthem have proved entirely inoperative for the greater depths at whichdivers frequently do their ship salvage work. My invention involvesdiscovery and solution of all of the difficulties which have heretoforebeset such under-water metal cutting operations.

In torches of this kind, submarine or otherwise, the ratio of fuel gasto oxygen and its proper mixture must be carefully regulated in order toeffect the required preheatng of the metal and the cutting thereof bythe supplemental oxygenjet.

Heretofore it has been found extremely difficult and in practiceimpossible, to satisfactorily effect such adjustments under waterv forvarious reasons. It isy dillicult enough even in above-water Work. Thelow visibility under water makes it dillicult to see the apparatus andthe work, and it is still more difficult to judge the flame conditionswithin the bubbling air envelope. Furthermore, the combustion conditionsof 6o the jet are very different from those` in the atmosphere; Wherethe pressure is practically constant, it is 15 pounds per square inch.Under Water, however, even one foot increase or decrease of depth causesa change c5 of approximately 1/2 pound in the pressure the Water exertsupon the flame supply jets. Thus, at a depth of only 30 feet, thepressure is increased to l5 pounds per square inch above atmosphere,while at a workable depth of 180 feet, it is 90 pounds per square inchabove atmosphere. These multiplied pressures correspondingly multiplythe density of the gases in the flame within the bubble and also theback pressure on the jets which 'J5 supply the bubble. Consequently, thespeeds of the gases emerging from the torch are proportionally reducedwhile the speed of propagation of the flame is proportionally increased.For both of these reasons, so the liability of the torch t0 back lireincreases rapidly with increase of depth. As

a result it has been found impractical for a diver to properly adjusthis mixture under practical conditions of under-Water work'. 235Consequently, gas pressures for the torch have generally been controlledfrom abovewater in accordance with carefully prepared charts or tablesof depth pressures, for the fuel gas, for the oxygen, and for the air $0sheath, the basic pressure for proper operation at the shallowest depth,being determined by` a very careful test under laboratory conditions.While this is the best that can be done in accordance with the priorart, it proves `entirely unsatisfactory under vthe conditions ofpractical use by a diver where it is seldom possible to determine theprecise depth of the torch, either initially, or as the work progresses.Moreover, such Work under the same conditions and withv the same maximumheating effect. For this purpose, I employ a gauge and a test bar ofmetal that can be held at an exactly predetermined distance from the tipof the torch, in fixed relation thereto so that the diver can closelyinspect his jet and the effects of his jet on the metal. This makes itpractical to supply the submarine torch with adjusting valves to bemanipulated by the diver until the desired effect is produced on thetest bar. In this Work, an adjustable gauge for the test bar is mountedon the tip of the torch so that when the desired adjustment is attained,it is only necessary to displace the test barand place the gauge of thetorchl in direct contact with the hull of the ship or other metal to becut, whereupon precisely the same perfect heating effect will be had onthe work that was had on l the test bar.

An im ortant development is that thi method o testing and adjusting withlaboratory exactness under most trying underwater conditions, soonteaches the diver precisely what positions he should set his variousvalves, after he has once got started on any particular job, otheradjustments for substantially changed conditions being effected byresort to the test bar or to another novel method which I havediscovered. The latter discoveryis that the relation between the gasesused, can be easily ascertained at any depth by opening valves one at atime and adjusting each to get the proper length of bubble of each gas.For a proper mixture, the ratio of these lengths is Vconstant at eachdepth. Preferably, all

valves are marked so that the operator can note their individualad'ustments and can reset them to the require opening when all gases areturned on together.

' None of the pro osed under-water torches of the prior art isclose whatI have discovered to be the desirable relation for discharge of theprimary fuel gas and oxgyen mixture with reference to the jet for thecutting oxygen. The same thing is true of the air sheath, with referenceto the fuel and oxygen jets. I prefer to have the primary gas-oxygenmixture discharged through a circularly arranged set of parailei,relatively small jets and the cutting oxygen being discharged through acentral parallel jet. The air sheath jet is a thin annulus surroundingand discharging substantially parallel with the jets of the fuel-oxygenmixture and the cutting oxygen jet. lVith such parallel arrangement ofall the gas streams, turbulence is avoided and the air sheathsurrounding the fiame simulates and reproduces With satisfactory4approximation the combustion supporting relation of atmospheric air tothe Haine, in the operation of an above-water torch of similarconstruction.

Another feature' involves discovery that there are fundamental but moreor less obscure difficulties attendant upon use of acetylene and otherhigher carbon fuel gases, or mixtures, which have been supposed to beessential for under-water work, because their high caloriiic values wereconsidered necessary for properly preheating submerged metal. Acetylenegas, for instance, is unstable when used under pressures and may be verydangerous when employed in a torch at any considerable depth. Whensubjected to depth pressures near and above 15 pounds above atmosphere,it is likely to detonate or decompose explosively, a danger entirelydifferent from and less understood than the ordinary blow backexplosions to which ordinary oxygen blow pipe mixtures are liable. Otherof the high carbon gases and mixtures are subject to the same and otherpractical difiiculties resulting from the pressures under which theymust be supplied to the jet. Freezing up is a common difficultyattendant upon the use of these gases. While various features of myinvention are applicable to the use of such fuel gases, particularly atsmall depth, an im ortant discovery is that substantially pure ydrogen,though it has far less fuel value, is of all others, the one that can besafely used at the greatest depths. Moreover, when properly used inaccordance with my invention, its fuel value and heating effect areentirely suiiicient for underwater work. These discoveries reverse theteaching of the present-day art.

The above and other features of my invention will be more evident fromthe following description in connection with the accompanying drawings,in which Fi l is a side elevation of a torch and attac ments inaccordance with my present invention;

Fig. 2 is a view partly in section, showing the various supply pipes andair sheath nozzle in axial section in the plane of the paper, the burnertip being shown in elevationg Fig. 3 is a section on line 3 3, Fig. 2;

Fig. 4 is a vertical ction through the burner tip in the same plane asFig. 2;

Fig. 5 1s a detail view of the test bar and attachment for the torch;and

Fig. 6 is an elevation of the gauge viewed at right angles to thedirection shown 1n n these drawings, some of the structural features ofthe torch may be substantially the same as found in certain makes ofabovewater torches but never in under-Water ltorches so far as I amaware. As concerns the burner tip and certain other features n 6 suplied from oxygen hose 7; and pipe 9 for t e cutting loxygen which isalso derived from hose 7 but separately controlled by means of valvetrigger 10. As will be evident from Figs. 2, 3 and 4, the hydrogen ipe 2discharges into annular cavity 11, in iiead 12 and thence through radialholes 13 to the parallel fuel-oxygen nozzles 14, 14. The oxygen frompipe 5 passes into the annular space 15, which is cut oil' from 11 bycontact of collar 16 with the contracted walls within the head 12, andfrom said, annular space 15 the oxygen flows through radial holes 17,into each of the same jet forming passages 14, 14, that are sup liedthrough the hydrogen inlets 13, there eing an oxygen inlet 17 and ahydrogenY inlet 13 for each of said passages 14.

The cutting oxygen from pipe 9 is dis-I charged into cavity 18 in thebase of lsaid head 12, and Hows thence through the axial passage 19,around whichthe oxyhydrogen jets 14 are circularly arranged.

The improved attachment for affording lmy novel air sheath incombination with the flame jets 14, 14 and cutting jet 19, includes anexterior jacket or nozzle which may comprise a screw-threaded baseportion 20, adapted for clamping engagement with the annulus 21 of theabove described oxyhydrogen nozzle. This air sheath nozzle includes acylindrical jacket portion 22, surrounding and of substantially greaterdiameter than said. jet nozzle, to afford an annular interspace 23 ofsubstantial cross-section, permittlng relatively slow non-turbulent flowof the air up to a point 24 near the 'tip of the nozzle. Here thecross-section of this annular air-passage is greatly reduced, as shown.In this reduced portion, theinner wall 25 of the air sheath nozzle isapproximately cylindrical and the tip of the nozzle at 26 is near'enoughcylindrical so that the air sheath jet is discharged approximatelyparallel with the jets from passa es 14, 14,

which latter are to be rotected an supplied with air by said air s eathjet. The air is supplied to annular space 23 through a pipe 27, securedat one end by a gastight union 28, to a nipple 29 screw-threaded incollar 20 as shown, and at the other end b a union 30 secured to a valve3l supplie through pipe 32 and hose 33. The air sheath supply pipe 27and its connections 31, 32, 33 are held in fixed relation to the handle1 of the torch by collars 34, 35 detachably secured about said handle.The jacket thus constructed distributes compressed air or other similargas in a uniform stream around the tip of the torch in a directionparallel with the flame and oxygen jets and at a sufficient pressureentirely to displace the liquid from ltheI vicinity of the torch tip,and to form a proper cavity of air, free of liquid in which ignition andcombustion of the gases to be burned can take place. The chamberkdiameter is reduced near the end of the tip, so that the air is forcedto escape as a film completely surrounding the tip. The length of thejacket is required to be from about 1A inch longer than the tip to l@inch shorter; a jacket materially longer than this will prevent properpreheating of the metal b cooling 1t and one materially shorter wilallow the film air to escape without properly protecting the flame fromthe liquid. A long jacket will also cause the compressed air to mmglewith and dilute the pure oxygen 'discharged through the cutting hole inthe tip and make cutting impossible. The valve rovided on or in thevicinity of the torch andle so that the operator may adjust the pressureof the air supplied to the jacket so as always to maintain a film of airaround the tip properly to protect the flame, regardless of the depth ofliquid, friction in hoses, and variations in pressure ofv the air supplyat the surface, provided only that an excess pressure of air bemaintained on annular space 23.

- My novel gauge as shown in Figs. 1 and 6 includesfingers 36 extendingparallel with the axis of the burner nozzle, having end gauge surfaces37, in a plane at right angles to said' axis. The auge fingers are madeadjustable axially o? the jet, preferably by making them integral with ascrew nut 38 engaging threads 39 on exterior of the air sheath nozzle.VSuch an adjustable gauge or spacer is ractically essential inunder-water work to .'eep the tip of the torch at the adjusted to suitthe condition at the depth at which cutting is to be done.

j While this gauge construction and mounting is new and useful fora'diver highly experienced in the use of my apparatus in accordance withthe above described methods, I prefer to provide, even for theexperienced diver, a means for supporting a metal test bar 4() in fixedcontact with the gauge surfaces 37 of gauge fingers 36. Aconvenient andsimple form of clamp comprises members 41, 42 formed at their outer endswith opposite edge clamps 43, 44 engaging the test bar 40'. At theiropposite ends, they are formed for detachable engagement with the torchstructure. The portions 46, 47,

straddle the pipes 9, 5, 2 and 27, said pipes being preferably all inthe same plane so that the plane of the cla-mp and the bar held therebyis substantially fixed. Preferably, the clamps 41, 42 are of springmaterial held together as by screws 48 and clamping nuts 49, 49,preferably designed so that the bar 40 will be securely but slidablyheld in 'the clamping jaws 43, 44, while the mounting jaws 46, 47 willbe securely held to the pipes, for ready attachment or removal. Tofacilitate the attachment, the outer ends 46a, 47 a. are preferablycui'ved outward as shown.

-From the statement of the nature and objects of my invention, firstabove given, the uses of the above described apparatus will be obvious.The above-water source of supply through hose pipes 3, 7 and 83 requiresno special cont-rol provided only the pressure be in excess o themaximum pressure required at any depth at which it is proposed to Work.The diver will first turn on and adjust one ofthe gases as, forinstance, the hydrogen, to get a suitable length of cavity in the Waterland will then note the proper setting of the valve which he thencloses. He will then do the saine thing separately for the oxygen andfor the air, adjusting for the length of bubble of each which he knowsby experience will be necessary for the predetermined adjustment of thehydrogen. Then turning on all the valves to the predetermined settivng,the mixture may be ignited in any of the usual ways as by an electricsparker inserted in the bubble. The test bar may be applied as shown inFig. l sothat in full view and at closest range the diver may furtheradjust the oxygen and hydrogen by means of valves 4 and 8, until theflame is exactly right and heats a white hotspot on the bar. If desired,he may then test the oxygen cutting jet by manipulation of trigger l()to cause combustion of the liron or steel. Having thus attained desiredoperation on the test bar at the desired depth, he will then apply thetorch with the gauge surfaces 37 in contact with the metal to be cut,with the certainty that maximum heating and cutting effects will beobtained. The

test bar and method of using the same is not specifically claimedherein, being reserved for another application.

It will be understood that an under-water torch constructed inaccordance with my invention will be of great use in many otherindustrial operations besides salvaging ships and the like. F orinstance, the torch may.

be used by a fireman for cutting girders, etc. during a fire, while theyand the torch are protected from the fire by floods of water from thefire hose; or, the torch may be used indiscriminately for cutting metalabove or under water in a cellar which has been Hooded in attempts toput out the fire.

A more conventional commercial use constituting a distinct invention, isthe shaping of refractory metal castings as, for instance, chrome steel,by subinerging such castings in a suitable liquid and then using mytorch for cutting the submerged casting to shape. In this way, the heatmaybe localized so that the cutting torch can be used to shape thesurface, yet the liquid will confine excessive heating and damage ofquality to a very thin layer of the metal adjacent the cut surface,leaving the rest of the metal unaffected. For this purpose, hydrogen gasgiving a temperature somewhere near 2,500 F. is distinctly preferable toacetylene, which gives temperatures nearly 1,000 degrees higher.

, I claim:

l. An under-water cutting torch having a burner nozzle for discharge ofan oxygenfuel gas mixture, a substantially cylindrical sheathterminating in a nozzle for surrounding the same with a sheath of air orthe like, in combination with a gauge mounted for adjustment lengthwiseof said burner nozzle, said gauge comprising diainetiically oppositeportions of equal length projecting endwise beyond the nozzle andendwise adjustable by a screw-threaded mounting on said nozzle.

2. An under-Water-cutting torch having a burner nozzle for discharge ofan oxygenfuel gas mixture, a nozzle for surrounding t-lie saine with asheath of air or the like, the passages for discharge of the oxygen, thefuel gas, and the air, being approximately parallel in combination witha gauge mounted for adjustment lengthwise of said burner nozzle, saidgauge comprising diametrically opposite portions projecting vendwisebeyond the nozzle and having a screw-threaded mounting thereon, andmeans for independently supplying and adjustably controlling oxygen,fuel gas and air to cool the torch nozzle.

3. rlhe method of adjusting an oxygenfuel gas flame surrounded by an airsheath, for under-water cutting, Which method includes adjusting theproportions of the gases by separately and successively projecting andadjusting the pressures of uuignited jets of each, at substantially thedepth at which the cutting is to be performed to obtain a desired ratioof lengths for the respective bubble cavities formed by'each gasseparately, then simultaneously supplying all of the gases to their jetsat the respective pressures thus predetermined. j

"1. The method of under-Water cutting of metal, which includes producingand maintaining a flame of minimum turbulence by supplying the mixtureof gaseous fuel and oxygen to the flame through a plurality of parallelcircularly arranged jets, protecting said jets and the flame by asurrounding air jet discharged approximately parallel with said jets;and adjusting the proportions of the gases b jecting andyadjusting thepressures of unignited jets of each, at substantially the depth at whichthe cutting isto'be performed to obtain a desiredratio of lengths forthe respective bubble cavities formed by each gas separately, thensimultaneously supplying all of the gases to their jets at therespective pressures thus predetermined;

Signed at Westfield, in the county of Union, and State of New Jersey,this 15th day of November A. D. 1927. y

EDWARD ELLSBERG.

separately and successively pro-

